When at last a grayish light appeared on the horizon, it revealed a tangle of human shapes, heads sunk deeply between the shoulders, crouching, piled one on top of the other, like a cemetery covered with snow.
How is the comma after “other” being used in the above sentence?
A. It connects two independent clauses into a compound sentence.
B. It introduces a phrase that provides further information.
C. It separates adjectives in a series.